Changes in labscript suite v3

Upon migrating the code base to GitHub and publishing distributions on PyPI in April–May 2020, existing users should be aware of the following recent changes.

Profile directories

The labscript suite profile directory, containing application configurations, logs, and user-side code, is now located by default in the current user’s home directory, e.g. for a local user named wkheisenberg this is:

  • C:\Users\wkheisenberg\labscript-suite on Windows.

  • ~/labscript-suite or /home/wkheisenberg/labscript-suite on Linux and Mac OS X.

A typical structure of the profile directory is:

    ~/labscript-suite/
    ├── app_saved_configs/
    │   ├── default_experiment/
    ├── labconfig/
    ├── logs/
    └── userlib/
        ├── analysislib/
        ├── labscriptlib/
        ├── pythonlib/
        └── user_devices/

This structure is created by calling the command labscript-profile-create in a terminal after installing labscript-utils (per the installation instructions).

Note: As of labscript-suite/labscript-utils#37 an editable installation can be located within the labscript-suite profile directory.

Secure communication

Interprocess communication between components of the labscript suite is based on the ZeroMQ (ZMQ) messaging protocol. We have supported secure interprocess communication via encrypted ZMQ messaging since February 2019 (labscript-utils 2.11.0).

As of labscript-utils 2.16.0, encryted interprocess communication will be the default. If you haven’t already, this means you’ll need to create a new shared secret (or pre-shared key) as follows:

  1. Run python -m zprocess.makesecret from the labconfig directory.

  2. Specify the path of the resulting shared_secret in your labconfig. For example:

    [security]
    shared_secret = %(labscript_suite)s/labconfig/zpsecret-09f6dfa0.key
    
  3. Copy the same pre-shared key to all computers running the labscript suite that need to communicate with each other, repeating step 2 for each of them.

Treat this file like a password; it allows anyone on the same network access to labscript suite programs.

If you are on a trusted network and don’t want to use secure communication, you may instead set:

[security]
allow_insecure = True

Notes:

  • Steps 1 and 2 are executed automatically as part of the labscript-profile-create command. However, for multiple hosts, step 3 above must still be followed to ensure the same public-key is used by all hosts running labscript suite programs.

  • There is an outstanding issue with the ZMQ Python bindings on Windows (zeromq/pyzmq#1148), whereby encryption is significantly slower for Python distributions other than Anaconda. Until this issue is resolved, we recommend that Windows users on an untrusted network use the Anaconda Python distribution (and install pyzmq using conda install pyzmq).

Application shortcuts

Operating-system menu shortcuts, correct taskbar behaviour, and environment activation for the Python GUI applications (blacs, lyse, runmanager, and runviewer) is now handled by a standalone Python package desktop-app (per installation instructions above). This currently supports Windows and Linux (Mac OS X support is forthcoming).

Lab configuration

The experiment_name item has been renamed to apparatus_name in the labconfig (.ini) file, to better reflect the distinciton between the infrasturcture that experiment shots are executed on. The old keyword can still be used for this item, but a warning will be issued to remind you to update your labconfig.

Source code structure (developer installation)

Existing users who move to a developer (editable) installation, please note the following structural changes to the labscript suite source code:

  • Each package has a top-level folder containing setup.py and setup.cfg used to build a distribution from source. The functional code base now resides in a subfolder corresponding to the name of the Python module, e.g. an editable installation might contain folders:

    <path-to-your-labscript-installation>/
    ├── blacs/
    │   └── blacs/
    ├── labscript/
    │   └── labscript/
    ├── labscript-devices/
    │   └── labscript_devices/
    ├── labscript-utils/
    │   └── labscript_utils/
    ├── lyse/
    │   ├── lyse/
    ├── runmanager/
    │   └── runmanager/
    └── runviewer/
        └── runviewer/
    
  • Package names (shared by repositories and top-level folders) are now hyphenated, e.g. labscript-devices and labscript-utils.

  • Module names remain underscored, e.g. labscript_devices and labscript_utils.

  • The mixing of hyphen and underscores is inelegant but conventional.

  • All references to blacs are now lowercase.

  • As installation no longer requires a separate package, the repository formerly named ‘installer’ has been renamed to ‘labscript-suite’, and is a metapackage for the labscript suite (installing it via pip/conda installs the suite).

Versioning (developer installation)

Aside from the maintenance branches described here, versions of the labscript suite packages are introspected at run-time using either the importlib.metadata library (regular installations) or setuptools_scm (developer installations). Thus any changes to an editable install will be traceable by local version numbers, e.g. editing the released version of a package with version 2.4.0 will result in 2.4.0dev1+gc28fe94, for example. This will help us diagnose issues users have with their editable installations.